1. Field of the Invention
The present invention relates to a novel peptide having osteogenetic activity and an osteogenetic accelerator containing the same as an active ingredient.
The peptide of the present invention, which has the osteogenetic activity, is useful for treatment of fractures, as a filler in deficient sites of bone, for inhibition of decrease in bone substance related to osteoporosis and periodontic diseases, for prevention of fractures associated with osteoporosis and rheumatoid arthritis and the like.
2.Description of Related Art
Bone morphogenetic protein (BMP) is a member of transforming growth factor (TGF) β family (Wozney, J. M. et al, Science, 242, 1528 (1988)), and its active form exists as a homodimer having a molecular weight of about 18 kD. BMP has the function of acting on undifferentiated mesenchymal cells, inducing differentiation to chondroblasts and osteoblasts and effecting chondrogenesis and osteogenesis (Wang, E. A. et al. Proc. Natl. Acad. Sci. USA, 87, 2220 (1990)).
For this reason, BMP is expected to be effective in treatment of fractures, inhibition of decrease in the bone substance related to osteoporosis and periodontic diseases, in prevention of fractures associated with osteoporosis and rheumatoid arthritis and the like (for example, see Japanese Unexamined Patent Publications Nos. HEI 6(1994)-298800 and HEI 10(1998)-70989).
Also, there are known a number of inventions relating to implants and compositions in which BMP is combined with a variety of matrices (for example, see Japanese Unexamined Patent Publications Nos. HEI 6(1994)-296677, HEI 7(1995)-246235, HEI 7(1995)-116240, HEI 7(1995)-88174 and HEI 10(1998)-151188).
However, the above-described BMP, when it is administered in vivo, disappears from blood within a few minutes and loses its effect. If administered in a large amount for compensating that, BMP might possibly cause various adverse effects, including toxic effects on livers and kidneys. Further, BMP has an immunogenicity because of its large molecular weight, and might possibly cause anaphylactic shock when administered repeatedly. Furthermore, where BMP is impregnated in matrices of decalcificated bone or collagen for use, osteogenetic activity is expressed, but there may be another problem of antigenicity or infection attributed to the matrices.